Data/Floating.hs

   1 {-
   2  - Copyright (C) 2009-2010 Nick Bowler.
   3  -
   4  - License BSD2:  2-clause BSD license.  See LICENSE for full terms.
   5  - This is free software: you are free to change and redistribute it.
   6  - There is NO WARRANTY, to the extent permitted by law.
   7  -}
   8
   9 -- | Top level module for alternative floating point support.
  10 module Data.Floating (
  11     module Data.Floating.Types,
  12     module Data.Floating,
  13 ) where
  14
  15 import Prelude hiding (RealFloat(..), RealFrac(..), Double, Float)
  16 import Data.Floating.Types
  17 import Data.Floating.Environment
  18
  19 import Control.Monad
  20
  21 isInfinite :: PrimFloat a => a -> Bool
  22 isInfinite = (== FPInfinite) . classify
  23
  24 isNaN :: PrimFloat a => a -> Bool
  25 isNaN = (== FPNaN) . classify
  26
  27 isNormal :: PrimFloat a => a -> Bool
  28 isNormal = (== FPNormal) . classify
  29
  30 isSubNormal :: PrimFloat a => a -> Bool
  31 isSubNormal = (== FPSubNormal) . classify
  32
  33 isFinite :: PrimFloat a => a -> Bool
  34 isFinite = not . liftM2 (||) isInfinite isNaN
  35
  36 isNegativeZero :: PrimFloat a => a -> Bool
  37 isNegativeZero = liftM2 (&&) ((== FPZero) . classify) ((== (-1)) . signum)
  38
  39 -- | @fquotRem x y@ computes the remainder and integral quotient upon division
  40 -- of x by y.  The result is (x-n*y, n), where n is the value x/y rounded to
  41 -- the nearest integer.
  42 fquotRem :: RealFloat a => a -> a -> (a, a)
  43 fquotRem x y = (frem x y, nearbyint (x/y))